Grey Matters is back, and the computer troubles are now over! I thought I'd return to blogging with July's snippets.

• There's a new group of British street performers that are right in the spirit of Grey Matters. They're called Maths Busking and they entertain with mathematical feats, in an attempt to get more people to see how interesting and engaging math (or “maths”, as they say in Europe) can be.

There's a great Maths Busking intro video over at Guardian.co.uk (Flash required), and an amusing video of BBC reporter Ruth Alexander's turn at Maths Busking (Flash required) on the BBC site.

• Speaking of things that fit well within the spirit of Grey Matters, there's now a blog called New Mental Magic. It focuses on teaching easy ways to do math in your head. Give it a look.

• For those who like to keep their MAGIC Magazine database up to date, I've just added the information for the July 2010 issue of MAGIC. On that same page, you can also get data for issue from November 2009 through June 2010, as well. All the other data is available at the MAGIC Magazine link at the beginning of this paragraph.

• The July 2010 issue of MAGIC features a very large tribute section to the late Martin Gardner, including a look at the mini-column he wrote in MAGIC for many years. Even if you don't regularly read MAGIC, this issue is well worth picking up for Martin Gardner fans.

• If you haven't been keeping up with my Twitter feed (as seen in the righmost column of this blog), I've been posting a series of videos (and one text page, so far) teaching various memory methods. You can find the posts at these links: Part 1, Part 2, Part 3, Part 4, Part 5, Part 6, Part 7, Part 8, Part 9, Part 10

• Most readers of Grey Matters know that I have a special place in my heart for Pi, even going so far as to start this blog on 3/14. So, it was a little jarring to hear it suggested that Pi is Wrong! (PDF). The basic idea is that what we call 2*Pi should really be Pi, because of how most formulas involving Pi work out. Michael Hartl explores this idea further in The Tau Manifesto: No, Really, Pi is Wrong.

If all the talk of radians confuses you, check out BetterExplained's Intuitive Guide to Angles, Degrees and Radians.

• One last goody – the movie The Phantom Tollbooth is available online again for free! Instead of being in an unwieldy 14 parts, as it was previously, it's down to a more manageable 2 parts. Check out the movie, and enjoy!